Traffic were popular in the UK/Europe with their first albums with Dave Mason, but not so much in the US. The later 70s albums were big in ths US but did little business in the UK.
Kasabian. Huge in the UK, fairly unknown here in the U.S. I saw them at the Metro in Chicago (capacity 1,100) in 2014, the same year they headlined Glastonbury in the UK.
Ultravox were big in the UK during the early eighties, but were barely known in the States. The Jam, Kate Bush, The Style Council, Status Quo, Mud, Haircut 100, Kirsty McColl, Altered Images, Big Country and Alison Moyet were other British acts who failed to make much of an impression on the States. Some American/ Canadian acts like Journey, Boston, Styx, Billy Squier, Pat Benatar, Jefferson Starship, John Mellencamp, Loverboy and Night Ranger failed to make impact on the British charts as well.
The Cars had two top five hits in Britain with My Best Friends Girl and Drive, while Just What I Needed made the top twenty.
but not in Germany - Crimson and clover, Sweet cherry wine ,Crystal blue persuasion were all hits here
The OP said "Thinking of huge 'Stadium' bands that are big in America but barely sell out a Theatre in the UK." I don't think any of those were big touring acts here were they? Besides, the idea is to compare US popularity to UK popularity. Survivor had only one charting album in the UK (reached number 12). How is that decent success? REO Speedwagon had only 2 charting albums in the UK; one at number 6 and the other at 29. In USA they had 3 Gold albums and 5 Platinum albums (one of which went 9 x platinum). If you're thinking of singles, Survivor had only two hit singles in the UK and REO Speedwagon had three. You can compare the others for yourself if interested.
I take it back! I heard from a few boxers that fought at MSG who said it was smaller than they thought it would be. Maybe they were used to Las Vegas stadium sized venues?
There used to be a smaller venue inside the MSG complex called The Felt Forum, which was way smaller than the Garden arena. In the 70s and 80s, they had smaller boxing fight bouts there as well as small-sized music concerts there. I saw Chuck Berry there, and I doubt it held more than 1000 or 1500 people. So maybe that is what you are thinking of with regard to MSG being smaller than the Knicks basketball arena, which is the big venue in the MSG complex. The old Felt Forum has been completely redone and is now a theater.
Big Country had two big hits here: Fields of Fire and In a Big Country. Altered Images got play with Don't Talk To Me About Love. I had those records and knew about them from radio or MTV. I don't think either of those bands were headlining stadiums back home. You can correct me if I'm wrong.
I remember The low spark... and Shoot out .... being quie popular at the time in Germany , not chart-topping albums of course but neuther were their earlier ones if I remember correctly
Cheap Trick - but am not really sure igf they were popular in Europe or not - I have only heard one song and have never met anyone who owns a CT album
Bob Seger was quite popular in Germany in the late 197o's early 198o's , but this was a time when we still had AFN and most concert-goers were GI's
Those artists were probably better known at home but they were never "big artists "in th UK (or Europe) , can't imagine they ever played in front of more than 500 - 1000 people (festivals excluded)
I'm sure Bob has a fear of flying and hasn't left the US since the mid 70's. Not touring and associated promotion will have affected his popularity outside the US, but I continued to buy his albums!