While I am not willing to shell out huge amounts extra to support LDS, If possible I prefer to spend my money where I can go talk face to face about any issues that might occur with equipment, and feel that is worth a little extra $'s. YMMV
Where I live (Orange County, CA), there are only 3 dive shops within 30 miles that I actually enjoy going to, of those 3, only 2 I truly don't mind spending money at in the hopes they remain. Wasn't always that way, but shops sell to other owners who now own 5 shops in the radius, other shops close, etc. I find I don't actually feel good about going to most places because the service sucks and if I genuinely need assistance, I've either felt belittled or shrugged except they're happy to take my dollar. In the end, I have no desire to support those local shops and don't care one way or another what happens to them. In reality, it would affect me. Others I might want to dive with may frequent those places and I might be at a disadvantage for a buddy if the locale didn't have many dive shops but I digress...
When I first got certified, I bought into the shops hype that you need to buy from them and not shop online yada yada yada or you're doomed (DOOMED!). I dropped $4k for gear for me, and $4k for my wife, + some $K more for miscellaneous and improvements over the next year. I did get the 10% discount for being a club member. Now I know enough and there are things I won't buy online unless I get the manufacturers warranty (a computer is one, I've had my computer replaced enough times) and other things I'll never use a warranty for anyway so I may as well save money by going online.
While I'd like to keep shops in business, there are only two places around here I would like to stay in business (and they are both struggling) but they never have what I want or can't get it because they aren't an authorized dealer for the gear I want.
The other shops just don't feel friendly to me. A few I'm quite repulsed by. Won't even get free air fills there when given the chance. Since I constantly spend more and more on improving my gear configurations, training, specialties (soon to rebreather and cave), I care more that the shop has good service than whether my local grocery store does but price is becoming very important. Regardless price, I won't purchase from a well-price place that actively repulses me for whatever reason.
In the end, you do what saves you money, gets you a good deal, if the warranty is important to you, make sure you get a bonafied warranty, and feel no regrets. Live life. Don't lose your mortgage over this sport. Save money where you can.
Thanks,
Shawn