I wonder if that why British artists such as Davy Knowles and to a lesser extent the likes of Matt Schofield have re-located to the US, in order to make it easier to get US gigs. (Okay- I know it's not their prime reason....) We have to look no further than a couple of months back when Oli Brown's RavenEye did a pledge fund-raiser to help with expenses on their US tour supporting Slash; an idea that was first done by Marillion years ago - fans asked, the band said they couldn't afford and before you know it fan power had a collection and funded the tour... I know a few years ago, talking to Martin Lewis and the possibility of getting Virgil & the Accelerators over to the US and they were looking £3,000 each for visas alone; Martin had this cool idea of getting a couple of young UK bands together and re-creating the British Blue Invasion of the 1960's, fifty years on.
Several things to look at though, there's a number of upcoming bands in the US, such as Ty Curtis, who don't or can't seem to tour beyond a 2 or 3 State range - it's only recommendations such as the forum produces, that get them known beyond this boundary. You could almost say the same for Ryan McGarvey but somehow, he's managed to leap over the Atlantic and does more gigs, 3 months in Europe than he does the rest of the year in the US...
Turning that last point slightly; there are a lot of great bands touring mainland Europe that we somehow never see play over here in the UK, while this "freedom of movement" still exists, yet plenty of UK bands hit the Europe trail, especially Germany, Austria; Belgium & Netherlands, with Spain, Poland & Czech Republic becoming more receptive markets.
One last thing I wonder, and its a bit of a pet peeve with me, is it purely financial, the number of US bands who come over here and do a UK tour of London? We may not be a big country, but we can't all jump on the train and fit into The Borderline, Jazz Café or even Shepherds Bush O2 at the same time. That said, certainly grateful to those who manage to call round, there's some crackin' bands touring, just a shame it does seem to be a one-way-trade.
When life gives you lemons; don't make lemonade.
Give back the lemons. Why were the lemons free? What's wrong with the lemons?
Do Not trust the lemons...