I did some further testing with several devices

0x2b03 (camp and caravan site default style)  renders on Dakota, Oregon 600 as tent symbol, but is not findable at all. On a Nuvi 310 it renders as tent and findable under lodging

I adapted the default style and made a test map without typ file

0x02b05 tourism=caravan_site

0x4800 tourism=camp_site

0x2b05 = renders on Dakota, Oregon 600 as tent symbol, and is findable under lodging/campgrounds. On the Nuvi it renders as "bed" (lodging) and findable under lodging

0x4800 = renders on Dakota, Oregon 600 as tent symbol, and is findable under lodging/campgrounds. On the Nuvi it renders as tent, but pois are not findable at all

Please test it for other units.