To be honest lack of IPv6 support is a petty reason not to use them

For people like us (IPv6 advocates), moving away from IPv4-only services is just like voting with our wallet. Well, except that the flow we are looking at is not money flow, but internet traffic instead.

Obviously such a movement is not going to make a huge dent in the grand scheme of things -- very few people care about the internet protocol they are using. But the idea is that it will eventually end up in someone's log that, a lack of IPv6 support is driving customers away and/or implementation of IPv6 support is attracting new customers.

Also, it doesn't hurt anyone else except us when we purposefully move away from IPv4-only services even though the IPv6-capable services are worse ;) Anecdotally speaking though, that's a rare case.