I can't speak for all vendors, but your right to think that buying at that local place is higher, (and if your paying 10-17 bucks for a tip then your being ripped off for sure).....however there is another thing to think about. As a former store front/shop manager I got calls constantly from people asking me who I would recommend to do some cleaning. Guess who I always recommended without fail...?, Yeah one of a half dozen of my better customers that did that type of work. Yes I charged 6.50 for a tip, and yes I was doubling what I paid, but unlike some companies I had a store front, with overhead, and several employees, with families, and a community that I participated in. Now that I build machines for people and don't actively do these things anymore, I can afford to drop ship you some parts at 10-15% over cost. I guess my point is sometimes spending that extra 200.00 a year over what you would have spent will actually pay off in the relationship you build with you local supply company, you will have to be the judge of that.