One is free money the other is virtually free money. You have to deposit $50 on each site and bet your real cash not use a bonus bet but you can immediately withdraw the payout.
They had it on the NFL game last night too, max $50 1+ point is scored. Last 0-0 tie was 1943 so virtually free money. The other had $50 double up 1+ TD scored. ~550 games played last season and 2 had no TDs so something like 99.7% to win, virtually free money.
Wife and I bet all 4 bets each which is very likely to be an easy +$400 for us. UK could get shut out and without checking the stats I'm sure that's highly unlikely too so I'm not worried about it.