Costs more to take the bus in to town than it does for most (slow) deliveries.
For some things there are no bricks and mortar stores left. I wanted test cables for a multimeter. 20p from China! (takes weeks mind you); I spent about £3 to get some delivered from a company in Europe within 2 days (probably drop-shipped from China) ... I can't think of anywhere in my UK city to buy them.
Bus for me and my toddler in to town and back is £2.80+£1.40 (it's about 3 miles).