You should because many collectibles are valuable and with inflation rising collectibles also tend to rise in value.
Unfortunately many standard homeowners and renters insurance policies either omit collectibles or have ridiculously low insurance limits on those collectibles. So in case of a fire or flood (common threats in Southern California) your regular insurance limits could be $500 or less on your prized oil paintings, china, crystal, comic books, and classic toys. You need to discuss your collection with your insurance expert. You likely will find that the fine antique furniture you have from the 1800s isn't insured under your regular policy but that sofa from Costco is. To add certain collectibles you may need a written appraisal. When an appraisal is needed will vary with the value and with the policies of certain insurance companies. King Richard's has experts who can give you appraisals. Sometimes insurance companies will accept paid receipts as a proof of value. Here's a tip: take photos of your collectibles and keep those photos as well as appraisals in a bank safety deposit box. It makes no sense to keep those records in your home because a fire or flood can wipe out the collection and the proof at one time. Photos are very important because few collectors keep a detailed inventory of everything they have so photos can help you remember when you file a claim.