I don't think you can really classify it as front running. Technically, the only information, that the alleged front runner in this case has over the followers is the knowledge of the trade itself.
Knowledge of the trade may indeed be share price sensitive information (for some high volume traders or those respected and with many followers) but it's not really like they can't know about it before everyone else; parity isn't possible in this case.
If an company/organisation (i.e. the social trading platform say) responsible for disseminating the details/log of a trader to a following (or individuals working for said company/organisation), were to act on the trading data before dissemination then THEY would be guilty of front running.
The alleged front runner may profit from the following of course, but that's only really occurring due to the publication of information that is share price sensitive, and such information generally has to be published by law (if it is by law so classified) so it's difficult to find too much fault. There has to be a certain amount of consideration on the part of any trader as to who is more the fool, the fool or the fool that follows them?