There are some differences. Scanners are designed for the purpose of scanning large numbers of frequencies, usually public service and aircraft. Therefore, scanning speed will be pretty high. Also, scanners usually omit certain frequency ranges. Nobody is going to scan broadcast stations, so scanners usually omit all broadcast frequencies. Scanners (almost) never receive anything below 30MHz. Usual is three bands: around 30-50MHz, around 110-180MHz, and around 400-500MHz, and some may offer around 800MHz to 900MHz. This leaves out: shortwave, CB, AM broadcast, FM broadcast, TV audio. Some of the more expensive scanners can also receive digital and trunked police bands.

A DC-to-Daylight strives to receive as much of the spectrum as possible, including AM/FM/TV/shortwave. Scanning speed may not be quite as fast, and forget about monitoring any digital transmissions. But I would much rather have one of these.