Good on you for being a collector that is awesome you are a true music fan.
But here is my point:
I know true fans will collect. I know what your saying though for general new releases top 40 etc, cds are redundant formats. But the general misconception is when you buy a CD from a store you are supporting the artists - no you are supporting the record companies and distro generally very little goes to the artists a much high % goes to the artist from digital distro.
Buying online - more will go to the artist (plus you will more than likely get a better price). If you buy from a retailer like JB Hi fi for example then a % of your sales you are paying staff wages, annoying junkmail catalogues, rent, staff, management, security gaurd, store fixtures, their stereo that blasts annoying music, etc wtc. if you buy online more will go to the artist due to less overhead and less links in the supply chain.
Some real world stats:
low end royalty deal
Retail Revenue label: Artist
$9.99 $2 $0.30
High end royalty deal
$9.99 $2 $1.00
online physical sale (eg CD Baby)
$9.99 $0.00 $7.50
Can you see my point? Please shop online for physical CDs, anyone who has access to the internet but still buys from places like JB Hi FI when around only 30 cents for every $10 spent goes to the artist - wake the hell up this is a disgrace!
Sure build your CD collection I do that too - but be mindful where you purchase from if you want the artist to benefit as well.
That is one of the reasons i started an online store, which i hope you can support with all your metal might.