This must be a cultural thing as that simply wouldn't happen in the UK - if someone asked for my number in a shop i'd tell them no flat out...i get enough cold calling and 'wrong number' calls to want to be phoned by any more strangers.

You definitely need to look at finding friends in areas where there's more common ground - go along to hobby classes, sports activities, or even a bar etc. I think it's great that you want to be friends with people and try to be proactive about it but there's simply better ways of doing it. These days i think the description of friendship has changed - peoples standards are a lot higher, more is expected and there seems to be pressure for longer term companionship that most people can't offer. As long as you're aware of your own expectations - and make it clear to others too, you'll avoid a lot of disappointment. In the meantime, are there older friends you can meet up with? Even if you only see a couple of people a month, that's a pretty good start.