Well, there are many reasons for stacking. Simpler management of the stacked device, less configuration, one less device to backup and restore, being able to utilize multiple links across the stack without having needing to support mLAG, easier to upgrade code, easier to find ports in the stack, as all the ports in the sack of the switch number before the port number, i.e. 3:5 is switch 3 port 5 and 5:3 would be switch 5 port 3. Makes mistakes less likely.
What you loose is, the ability to upgrade each switch, one at a time. Possibly minimizing outages or disruptions. I think a much better design for a ToR solution or end of row / middle of row switching... But for IDF's (switch closets for end user connectivity), it's just cheeper, and more efficient. 8 switches in 1 stack count as 1 license in NetSight (Extreme Management), vs 8 license if each of those switches were independent.
