Wow, great insight Fireant.
Nearly had to move our U12G home game this weekend to MPSC due to lack of willing ref to adjudicate one game at our location. Luckily we found one and game on but it points out there is more than a patch of grass to consider. If we moved this home game it would not have been our choice.
While on subject, if you are a ref and live in Clements Ferry/Hwy 41 area drop me a line and I'll make sure assignor has your name.
There are very good financial (business) reasons to host games (concessions, etc) and these easily supply more revenue than the field expense. It is not unusual for a club with several fields in operation to make hundreds of dollars on a weekend.
Next... good post Bear with regard to field maintenance. Additionally you would need to consider whether the additional matches on club 'rented' fields actually increases the host Club's cost (the City or town I suspect just charges a flat rate regardless of traffic). If in the rare case this happens you would then need to consider only the delta in cost as a legitimate charge.
So why pay fees to a host club if they don't actually pay more for field maintenance?
Finally Bear please don't read anything on this thread that is directed at Cainhoy or MP. Our names were thrown out as examples and I believe Shades is associated with JIYSC based on earlier postings. Since as you say they own their own fields, I suspect they have clauses in bylaws or operating rules that dictate when and if their fields can be rented or used. We do.
Then I would ponder where would a nonprofits fields come from. As a public charity if these were donated you would have to at least consider the donors intent in any land contribution and ask whether they would want the field held for exclusive use or shared by many. In any case, this topic is complex and would need to be handled on a case by case basis in my humble opinion.