Most actual recluse bites* occur in the home, for the reason that recluse are both very reluctant to bite and have a darn hard time forcing their tiny fangs into your skin even if they DO want to bite you. Most bites occur when recluse get into clothing that is then put on by the victim, squashing the spider against their skin.
It should be clear why this is a lot less likely to occur in a UL camping situation.
1-2 spider bites per night could, I suppose, be attributed to wolf spiders. I love turning on my headlamp in a dark forest and seeing hundreds of tiny little eyes shining back at me; even the tiniest wolf spiders give a pretty good eyeshine. That said, most spider bites are not actually spider bites, which brings me to the asterisk above...
*based on findings by arachniologists and medical researchers who actually study these things, the vast majority of diagnosed "brown recluse bites," particularly those that are diagnosed with no witnessing of the bite incident itself, are just necrotic skin infections with no relation to spiders. A little splinter or shard of fiberglass with the right bacteria on it gets under your skin unnoticed, and before you know it you've got a little necrotic lesion and the doctor says "yup, recluse." That little lesion might even expand and melt a good chunk of flesh away. Regardless of the old "white dot" myth, it's impossible to reliably differentiate between bite and infection without a tissue biopsy that turns up spider-venom proteins. Actual bites are often made much worse than they otherwise would be due to secondary infections. Recluse bite diagnoses were found to be common even in geographic regions where recluse are not present to be biting people.
So maybe spiders are biting you, maybe you're just getting pricked by tiny nonsterile sharp things while you hike and noticing the "bites" after your immune system reacts and makes an itchy little bump overnight.
Just in case I seem entirely too serious about these things, I have a history of nerding out just as much over the science regarding venomous spiders in North America as some here froth over the hydrostatic head of exotic fabrics and etc. Considering going to school for entomology, we'll see.