I'm pretty confused about people talking about house edge increasing or decreasing here. The more you bet, the more edge you give up. How you bet doesn't matter. If you want to give up the lowest edge while having a chance to win something decent, do small bets with small odds to win.
It looks like you understood house edge concept wrongly because house edge is constant whether you bet a small amount or big amount. House edge on this site is 5% so from your bet amount site will take 5% that means if you bet bigger amount then the house will get big amount but in terms of percentage, it is same.