Professional registrants use professional services
Price is not too big at GoDaddy if you use their domain club, which cuts it to around $7 for a dot com. One annual fee of $90 and unlimited registrations. Otherwise, it is like camel's nose under tent. One discount for initial registration, and then full price every time after that.
I mostly use BulkRegister (BR), cuz of ease of use. Their magic folders cut the time it takes to manage large numbers of similar domains. At BR they are not trying to sell you things at every turn. I've never had an issue with their lookup data being insecure. BR is for professional registrants. Ease of transfer out is much better than GoDaddy, especially after you've just sold a domain. GoDaddy has lock-ins and other nonsense.
BR also uses DLS for single registrations, compressing primary and secondary markets into one. Good for sellers. Good for buyers.