Your rules are arbitrary nonsense. There's a difference.
Level doesn't matter remember? Sunday League. Doesn't matter a damn. All that matters is a local team for local people.
Stadium, facilities, professional standards of play, excitement ... a real fan craves not such things.
You can't support Bohemians if you are from Glasnevin, because ... Tolka Rovers. You're not supporting your local team. How could you support two local teams? Makes no sense.
By your rules there's a tiny tiny tiny number of real LOI fans. If you're not in walking distance to the ground then you are probably not a real fan.
By supporting Bohs you are contributing to Irish football, contributing to facilities, contributing to the concept of there one day being a full-time league in this country to produce competent internationals instead of relying on England to do it for us.
By supporting Tolka Rovers you are again supporting one layer below, to feed well-coached competent young footballers into the senior level.
(1) They're not mutually exclusive,
(2) Junior football in this country is actually extraordinarily well supported and reasonably well-run
(3)it's much easier to point out the financial gap between a trip to England and the effect that cash could have on LOI football than it is to point out some bizarre gap between supporting an LOI team and a junior level team