This is a perpetual problem with most guilds. Many guilds, especially smaller ones, don't do raffle quilts because of the work involved in selling tickets. Some guilds require that the members donate a certain number of hours per year, in addition to paying dues, but I don't think this is quite fair since some members are unable to help out (physical limitations, work schedules, family issues, etc.) and they should still be allowed to be part of the guild. Some guilds have a drawing at the end of the fundraising, with each member's name being entered once for each hour served. (I won a quilt that way, but the possibility of winning didn't influence the number of hours I put in for the event.) Some guilds only do a raffle quilt every 2nd year, so the members don't get quite as burned out on the work involved.
It might be time to look for another fundraising idea, or raise the dues to cover part of the deficit. Perhaps the membership would like to stop the charity fundraising altogether and give to charity in another way, such as making quilts for a worthy cause, teaching quilting to children, etc.