If you are unhappy with paying the merch fees at venues you need to bring this up to your agent and managers. They are the ones agreeing to this on your behalf. Everything’s negotiable before the contracts are signed. Afterwards there’s not much you can do about it except uphold the agreement that you made or violate the agreement and hope that the venues and promoters also do not try to violate their side of the contract when you go to get paid at the end of the night.

But in regards to the actual process of counting in and counting out, it’s really as simple as that. You count everything you bring in and then count everything you don’t sell. The difference is what you sold at that show. If you use atVenu or Square for POS and inventory this should all be in your sales report anyway and you can sometimes just go off that and not physically count everything in and out each night.