They won't give you the feed without an affiliate account, and an active one. Bet365 will only let you have their feed after you generate 5 paying customers total if I'm not mistaken.
Feeds differ from one another substantially so with each feed you start working on the parser pretty much from scratch. And each bookie deals with these things differently - while some will give you the feed right away, the others will ignore you and leave you short (e.g. you'll get 17 out of 20 feeds). Like that stubborn last screw that's stuck.
Betfair's feed is particularly technically challenging, it's not like the others.
And even when you finally parse all feeds, you ought to match different team names from different feeds, e.g. Man Utd, Manchester Utd, Manchester United. Multiply by the number of teams and by the number of leagues, and then maintain on a yearly basis with new teams that come out of nowhere, e.g. Lincoln City gets promoted to League Two and therefore appears among your teams for the first time.
Technically very challenging. But there are ways. Your best bet is to just buy an already aggregated feed from an external provider, otherwise you'll spend a year just parsing the feeds.
Bookies don't mind attempts at beating them. In fact they welcome such attempts
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