The same way Russians fly from Tampere (the distance from St. Petersburg to Tampere is as much as 470 km), they'll be flying from Tallinn too (360km)
I tend to agree. Nevertheless, I wouldn't say the same about most of Western Europeans.
Myself, I could consider flying via Tallinn to, say, Helsinki, but the road travel from TLL to St. Petersburg would be frankly too far to be considered - except if looking for some kind of extreme adventure
. If - and I'm not so sure about it - Ryanair plan to encourage us to travel to Russia via anything in the EU, the only acceptable place seems to be Lappeenranta, situated less than 200 km from Sankt Petersburg. Any offer of that kind should however be carefully tailored for such a purpose. FR could evaluate e.g. providing the regular coach services from LPP to former Leningrad in co-operation with a local partner (coach enterprise/ travel office). I believe that giving pax a choice of further travel to Russia by coach in connection with the booking process would be a viable solution, worth trying. Otherwise most of the passengers will come from Russia only.