meh, locking the shares is only one of the 100 ways they could screw you if they weren't honest.
Seems you just don't understand what a contract means. Maybe because you're too young (or greedy or blind) for that.
EDIT:
Asking them to lock shares is frankly a vote of no-confidence and a blatant slap in the face and I'm ready for the issue to die.
No and no. That was a decision taken by Labcoin. Are you on Mars ?