Some shares break teleporting between worlds.
If you turn off bed_spawn in a share it simply refuses to teleport you to the target world and puts you back at your last known position.
There is currently no way not to share bed_spawns without breaking the access to entire worlds.

Take a look at this: https://github.com/Multiverse/Multiverse-Inventories/wiki/Big-List-O-Shares#last_location