HMRC allowed £6 a week without a full assessment. But yes, my commute is more expensive than my heating bill at around £75 a week. Food etc not so much, as I used to bring a flask and packed lunch ( public sector, so no free coffee and the only offering in the canteen is £2 a cup – kettles are banned as they use electricity….).
In life, it's not who you know that's important, it's how your wife found out.