There is a huge difference between $10 and $10 a month. "Afford" is not necessarily the right qualifier. Frequency of utility is pretty important here. My apple music sub costs $16 for my partner and I. We both use it extensively throughout the day. I might plan a new bike route once or twice a month.
If $10 per month or $10 once is an important amount, that means the person is broke. Like you explain yourself, it's not that you cannot afford the bike app, it is that the product is not for you, ie it's not worth your money. Most things are not worth our money. That doesn't mean we can't afford them.