Yeah. During a big Moscone event in late August, there are "cheap" hotels at the airport that were over $400 as of a month ago and very ordinary business hotels near the Moscone and Union Square were in the $500-$600 range when they had rooms available at all.

My personal sense is that San Francisco has gotten more expensive than New York or London. It obviously depends on what's happening at the time and where you're staying but I find with a little searching I can usually dig up reasonable-ish rates in New York and London. In San Francisco, if there's a big Moscone event (which tends to be when I travel there), it's hard to find much even on the other side of town.

London and NYC are significant larger, and have many more tourists per capita. They can probably absorb large events without it making much difference to the average price --s prices increase tourists book the week after, or a slightly different area.

Both also have good public transport, which makes hotels further from the event more appealing. (I don't know SF enough to content on transport there).

I don't know about tourists per capita but they're certainly significantly larger cities so most individual events don't cause the huge spike in hotel prices that something like an Oracle or a Salesforce show causes in San Francisco. That said, San Francisco is pretty expensive these days even if there isn't a huge show on just because of overall demand.

In general, public transportation in San Francisco isn't very good although it's really not very good to get to the Javits in New York either. However, the Fisherman's Wharf area and Nob Hill aside aside I'm not sure there's a huge amount of hotel capacity in San Francisco outside of a 10-15 minute walk to the convention center anyway.