Using vendor logic I should be buying cards from them at 70%
After all I have my own costs too. I paid entry to the card show, I had to pay for fuel to travel, maybe get accommodation depending on the location and prestige of the event. I'm suffering a huge opportunity cost by not working today and deciding to go to this card show, so I have to make sure I factor that in as well. Of course I have to eat, so there's a good bill attached. And let's not forget the tax we all have to pay whenever we make these transactions (lmao this one always gets me, what vendor is paying tax)
I'm also taking on a lot of risk when I buy from vendors. I mean I could be holding their card for months and during that time it could depreciate and I could get stung holding the bags. If a card falls in value then I'm out of pocket, not the vendor. I could have waited and bought 2 cards instead of 1. That's a lot of risk to be onboarding. In fact the vendors should really be grateful that I'm helping them out this way. I mean at the end of the day, without customers taking the time and effort to come to card shows and take the tedious time to sort through a vendors binder and look over their inventory for damaged cards etc. without us doing this they'd have no business to run.
Sure us Charizard collectors are a vendors bread and butter, we help them move cards quickly and easily and keep them in business. But without those faithful Goldeen collectors and the like, vendors would be swimming underwater. Without us niche collectors they'd have to actually hold their cards for more than a month! It's quite scary when you think about it for more than 5 seconds! We really are doing them a great service.
So really the way I see it, it's perfectly logical to only buy from vendors at 70% and not a penny more.