Good LBS's are a national treasure – and my LBS is great.
I use them for all kinds of stuff they don't normally have to try to get, and they'll happily try to get hold of whatever random nonsense I want – If they can't there's no messing about pretending the supplier is out of stock et cetera, they'll just say they can't get it.
If your LBS is crap they deserve to fail, but if they are giving it a go, help support them. The few quid extra you'll maybe spend flows back down the line in time, you'll get loads of advice, and / or discounts will start to appear on your invoices … 😉
Online is all fine and dandy, and I use the big stores for stuff I can't source via my LBS, but they'll be no good on the day I need a BB faced, or a bearing pressed out, or someone to hunt down an ancient obscure part …