[CSP2] Large CSP headers

Good afternoon,

I'm trying to make a number of API requests to an endpoint that has
excessively large CSP headers in the replies, and this seems like the best
place to ask about what to do.

In practice I'm going to be making a lot of API calls, and CSP headers have
become a bandwidth issue.

For example:
$ curl --http1.1 -Lis https://api.itbit.com/v1/markets/XBTUSD/ticker | wc -c
4474

That reply only has a body-length of 428, and the vast majority of the rest
are CSP headers.

HTTP2 doesn't help much, because api.itbit.com marks all header fields as
sensitive, so they skip the hpack table:
$ nghttp  -v --multiply=2 https://api.itbit.com/v1/markets/XBTUSD/ticker |
grep "recv HEADERS frame"
[  0.436] recv HEADERS frame <length=2925, flags=0x04, stream_id=13>
[  0.437] recv HEADERS frame <length=2842, flags=0x04, stream_id=15>

Is there a way to signal that the request is not coming from a browser so
these headers may be suppressed or at least reduced?

Thanks a lot,

--Ben