This should be the other way around.

If someone wants to join a guild. They should have the option to join guilds who have "recruiting" option checked in their guild settings.

You open up menu, guilds, join guilds,

[] tower
[] spar
[] chat
[] any

Looking for a guild...

Available Guilds:

Spar masters

spar assassins

girls royalty

You tapped on girls royalty

join?

[yes]
[no]

This would actually help a lot of people not have to promote "recruiting for xxxxx"