MyTime has been scheduling my electronics team for four and five hour shifts, so instead of hiring new people to fill the extra consumables and cashiering shifts, we tack on open shifts that like up with their scheduled shift to make a 7 or 8 hour shift for them.
Also with open shifts, only when shifts overlap does myTime actually want double coverage. So if I have a 6-10 and a 10-2 shift to fill, they both go to the same person. If I have a 3-8 and a 5-9, those shifts go to different team members, but the person on 5-9 might be working a 1-5 cashiering or hardlines shift before hand while the 3-8 is a cashier from 12-3. I don't know how other stores are handling it, but this is beginning to work for us. You don't necessarily need to hire a ton of new people to fill all he open shifts, you just need cross trained, available team members. If your team has severely limited availability and aren't cross trained on other areas, then yeah...you're probably going to have to hire a lot of new people and then everyone gets 15 hours a week.