Can a 85W MagSafe Power Adapter be used with my Macbook Pro 13 (Mid 2012)?

Absolutely! The gentleman at Frys is correct.

If you use a high-wattage power supply for any laptop, including Macs, that only requires a lower wattage power supply that is in fact better. The only downside is the greater cost, and the greater bulk.

FUN FACT! A savvy mac technician will always keep a single Magsafe (1) 85w power supply (along with a MagSafe->Magsafe 2 adapter) with them such that they can safely power various MacBooks made from 2006 onward until the USB-C models were introduced in the past couple/few years.

It's better strictly in the sense that it produces less wear and stress on the power supply since you are only pulling electricity through the transformer well below its rated capacity. As long as one doesn't mind the larger size/bulk and higher cost, it's better.

SlamDunk1978 wrote:

The folks at Frys told me that an 85W MagSafe Power Adapter could be used with my Macbook Pro 13 (Mid 2012)? Will this work without problems? They had no 60W units available.

Interesting you ask the question and you answer the question. 😉

Good computing SlamDunk1978.

SlamDunk1978 wrote:

The folks at Frys told me that an 85W MagSafe Power Adapter could be used with my Macbook Pro 13 (Mid 2012)? Will this work without problems? They had no 60W units available.

Yes, you can use it, not an issue— the machine regulates what it needs.

rcosta887 wrote:

<snip>

If you use a high-wattage power supply for any laptop, including Macs, that only requires a lower wattage power supply that is in fact better. <snip>

Please explain how using a higher wattage power supply is "... in fact better"?

Find the right power adapter and cable for your Mac notebook - Apple Support