I don't think this is a contactless thing as such, more that people don't realise that through tickets are available (which is a shame because through ticketing was one of the protections at Privatisation) . For example, someone travelling from Maidenhead to York will search for tickets from London to York with LNER often because they don't realise they can actually buy a through ticket from Maidenhead. To be fair train companies don't help by not offering through &connections Advance tickets on many routes.
When you have a Railcard, contactless should perhaps be avoided because it doesn't apply. That said and talking specifically about Maidenhead does contactless give additional rights to use the fast services during the evening peaks? Restriction codes on evening departures from Paddington specifically exclude the services that are non-stop to Slough or Maidenhead.
Yeah, that's true, although not relevant to any of the journeys I'm talking about as they'd almost always be on Saturdays. (If going to a weekday game it'd invariably be an overnighter). Contactless also has the benefit that you can double back at Reading if you want (although with the change a year or so ago to the regular Didcot Parkway train with the calling pattern Slough, Maidenhead... the double back at Reading is rarely quickest these days).