Those theaters labeled "noncommercial" or "nonprofit" are not immune from the financial diseases of the "commerical" or "profit" sector.

Last Sunday's report on ticket prices and why they're rising avoided what is happening with the non-profit groups across the land. While the symptoms are different the disease is as threatening - and ironic because the nonprofit sector was created to avoid the more obvious ills of commercialism. It seems imposssible just to create a theater for a community.

Arena Stage, nearing its 30th year, and the more recent Folger Theater Group are professional "resident" theaters, nationality admired and locally treasured. Yet both must devote time and money to details that might seem extraneous to producing plays for Washington consumption.

Because they are professional organizations, they must deal with Actors Equity, the national organization which protects performers' wages and working conditions. Both belong to the Theater Communications Group, created through a Ford Foundation grant in [WORD ILLEGIBLE] "to help raise standards and aid in the development of the nonprofit professional theater." Both are members of LORT, the League of Resident Theaters, devoted to the nitty-gritty of survival.

Last weekend in California, LORT had one of its periodic meetings with Tom Fichandler representing Arena Stage and Louis Scheeder representing his Folger Theater Group. While both used the term "routine" when asked if anything special had happened, both returned with only one definable comfort. They are not alone in their troubles.

Fichandler, whose pre-Arena career was in the foundation world, sees severe trouble ahead in the area of giants from public and private sources.

At one time such grants were viewed as "seed money," pioneered by the Kennedy Center's Roger L. Stevens. The root idea was "matching funds," that is, one organization promises X dollars if a theater can match that sum from some other source. It was a vital impetus toward creating and sustaining the performing arts.

Now, because it has been so successful, the "matching funds" concept threatens to become a monster. When a grant is made contingent on a performing group raising an equal sum independently, all the different performing groups become, in a sense, rivals.

While the public sum allotments have been rising, the private foundation figures have been falling. Though more private foundations now are recognizing the arts, their individual percentages have been falling off, partly because their investment holdings have been lowering in value.

Thus, to ensure that each matches the three-for-one figure promised by the National Endowment for the Arts, we soon will see local groups competing against one another. The more obvious contenders for the same dollar here will include not simply Arena Stage and the Folger, but also the Kennedy Center and its various subsidiaries, Ford's Theater, the National Symphony, Wolf Trap, the Washington Ballet and a score or so relatively modest performing groups.

Only true grace under stress will avoid open warfare between these like-minded groups.

Representing the smaller groups is the relatively new Cultural Alliance of Greater Washington, which will hold its annual membership meeting Dec. 7 at 3 p.m. in George Washington University's Marvin Center. There are over 150 groups and 100 individual members in the Alliance, headed by Delano Lewis of the Capitol Ballet. For information about this entire area, its monthly news sheet, Cultural Alliance News, is a stimulating, indeed valuable record.The subscription rate is a bargain $1.50 at Suite 419, 805 15th St. NW, Washington D.C. 20005.

If rising costs and fund-raising are a problem for organizations large and small so are some of the regulations intended to protect the artists.

At LORT's California meeting, one Equity stipulation stood out for sheer perversity.

Superficially, this seems at least fairly reasonable, requiring that should an off-off-Broadway "showcase" production lead to a second, more affluent one, the second must use the original "showcase" performers or pay them a three-week salary.

The intent is laudable enough, but in practice this will prove absurb.

Take, for instance, a playwright who is offered a humble Gotham "showcase." Performers he might wish for particular roles could easily be then unavailable, working either in New York or anywhere across the country. So, he settles for whomever can be found willing to work for less than peanuts.

At the same time, say Arena, the Folger or any professional regional theater may be considering the script, with its own company or particular players in mind. It could even be that the "showcase" production actually has inspired such plans.

But the regulation means that however incapable the showcase performers were, they must be assigned roles in the subsequent production anywhere it happens. If more skilled, even noted performers are hired for the roles, the initial players must be given three weeks' pay.

Thus, Equity has put itself in the position of penalizing regional theaters which, after all, now support more performers than the New York commercial sector.

Small wonder that Fichandler and Scheeder returned from their LORT meeting more chastened than cheered. With grants more complicated to match and with self-defeating regulations limiting new scripts, the nonprofit theaters have reason to be grave about their very survival. As Scheeder put it, "At least we came back with the feeling that we're not alone. There are a lot of us in the same boat."