Buying from a Supply House

Last night the second GE water heater since I bought this place went out. The first one lasted 1 1/2 years and the second 2. On both, the pilot wouldn't stay lit and I don't have time to mess around with such repairs. I decided it was time to roll different dice so I went to a local plumbing supply store that sells AO Smith. Everything is back up and running without problems, but I do have a silly question...

Is it considered to be bad form for someone like me (not a pro) to go to a supply house every few months and have someone spend 20 minutes fixing me up with a $50 order? They always seem cheerful and such, but it "feels" like I'm really wasting their time...

IF they do not ignore the professional plumbers while they do it, and if they do NOT sell to you at the plumber's price, then I have no problem with it.

'round these parts, only licensed plumbers can buy AO smith & Bradford White water heaters. Consider yourself lucky.

If my supplier sold to anyone without the proper license I would probably find a new supplier.