Who cares, stick them on there, if they come off, they come off.
Technically speaking, they "should" be ok. The speed of the water relative to the bottom of your board is "theoretically" zero, as friction creates a "no slip" condition on the wetted surface with a parabolic velocity distribution that is increasing from zero as you approach the free stream velocity. The scale of this sorta varies and there will be turbulence that is introduced, there are a few other parameters that I am not accounting for, but hey, they are stickers
This is essentially why you typically feel less wind when you lie on the ground vs. standing up and is also why windmills are up high