IMHO:
North Indian temples are congregational in nature like Mosques and Churches. In most temples in the North, one can actually touch the idols, do the poojas/atleast artis, etc.
Temples in South are of mostly Ritualistic in nature, especially Tantric temples in Kerala and Dakshina Kannada and to a lesser extent, most temples in AP/TS/TN/KA. Here only few individuals from ascertained and hereditary families are allowed to do rituals.
The latter concentrates power on a smaller group who can ensure two things - the quality of temples is maintained and commercialisation can be concentrated.
Is it good/bad? Depends on how the money is used. If it is used well, the temples will prosper. Else's the temples will just become a business.