Most new students go to a Flying School to learn to fly and get a licence to do so. As they probably have no idea what a LAPL is versus a PPL then they will perhaps be persuaded along economic lines. So far I have yet to see anyone who has achieved a LAPL in the minimum hours, so cost will be much the same whichever way you go and the decision will probably be later rather than early.
As there is really no difference in the training they receive and few if any students "enrol" on either course in a formal way, then we are left with the problem of the FI who is limited to teaching for the LAPL only, as we have no way of identifying it! All of course the product of botched regulation, with no constructive interpretation from any regulator, most of whom have little comprehension or interest in the issue.