Although some people don't like to watch football alone, that's why they usually go out to viewing centers where they can watch and argue with other football lovers too. From my observation, a large percentage of people who watch football at viewing centers doesn't have a subscription for the channels that will allow them view the match in their house. It's possible that they have television in their homes but they don't have subscription.
If subscription is the only problem as to why most go to viewing centres to watch football, then I think all the viewing centres will be less populated on match days compared to the way they usually are.
Even if someone doesn't have a subscription to their TV, they also have smartphones that don't always lack data; they can stream it online, and if the television they have at home is a smart TV, they can connect their mobile phone to the TV for a wider screen.
Let's also say subscription is the problem. If you calculate the cost some people spend on just watching football, you will know that renewing their subscription is nothing compared to that, as some buy drinks, carry friends around, and pay for transportation just to visit their favourite viewing centre.
I will say there is more fun they derive from watching with others compared to when they are home alone, while some people use that as an excuse to leave home.