Hey, I agree with you that if possible buy your gear from the shop, but if you're already set on buying boots online, I don't see any reason why you're fucking the shop to go in a try on a pair or two. It's better for everyone than not even go to the shop in the first place.
At least if you go in to try on the boots, you win by getting to make sure the boots you were checking out actually fit, and the shop wins because they're getting you in the door, and you're probably walking around and browsing the goods, which you would have never done if you just went straight to an online purchase. Chances are, even though you don't buy their boots, you'll spot some wax you need, or maybe a cool new facemask or beanie and make an impulse buy. Also if you go in there and the shop treats you well and you see some good gear for reasonable prices, you might consider going back there to purchase other items in the future. Only downside for the shop is that an employee has to grab a pair of 10.5s and maybe a pair of 10s from the back. What is that like 5 min?