Here Paul is not talking about the weekly 7th day Sabbath of the 4th Commandment, but rather, about the ceremonial sabbath days (plural). Look at the context of what he is discussing...the ceremonial celebrations, as we all know, were a "shadow of things to come". But the 7th day Sabbath stands with the rest of the 10 Commandments.
Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days: Which are a shadow of things to come; Colossians 2:16,17
EXAMPLES of sabbath(s) - Plural (ceremonial)
1) And it shall be the prince's part to give burnt offerings, and meat offerings, and drink offerings, in the feasts, and in the new moons, and in the sabbaths, Ezekiel 45:17
2) I will also cause all her mirth to cease, her feast days, her new moons, and her sabbaths, and all her solemn feasts. Hosea 2:11
3) And to offer all burnt sacrifices unto the LORD in the sabbaths, in the new moons, and on the set feasts, by number, according to the order commanded unto them, 1 Chronicles 23:31
4) Behold, I build an house to the name of the LORD my God, to dedicate it to him, and to burn before him sweet incense, and for the continual shewbread, and for the burnt offerings morning and evening, on the sabbaths, and on the new moons, and on the solemn feasts of the LORD our God.2 Chronicles 2:4
5) Bring no more vain oblations; incense is an abomination unto me; the new moons and sabbaths, the calling of assemblies, I cannot away with; it is iniquity, even the solemn meeting. Isaiah 1:13
6) Also in the fifteenth day of the seventh month, when ye have gathered in the fruit of the land, ye shall keep a feast unto the LORD seven days: on the first day shall be a sabbath, and on the eighth day shall be a sabbath. Leviticus 23:39
7) But in the seventh year shall be a sabbath of rest unto the land, a sabbath for the LORD: thou shalt neither sow thy field, nor prune thy vineyard. Leviticus 25:4
8) And thou shalt number seven sabbaths of years unto thee, seven times seven years; and the space of the seven sabbaths of years shall be unto thee forty and nine years. Leviticus 25:8
9) It shall be unto you a sabbath of rest, and ye shall afflict your souls: in the ninth day of the month at even, from even unto even, shall ye celebrate your sabbath. Leviticus 23:32