Before you start painting with that broad brush, you may want to take a look at the relevant statutory provisions.
I assume you’re referring to the Stolen Valor Act, which the Supreme Court of the United States struck down as a violation of the First Amendment. However, that provision did not have anything to do with the wearing of a uniform. It criminalised claiming to have received a military decoration, as summarised in the wiki article on the SCOTUS decision: “… a misdemeanor to falsely represent oneself as having received any U.S. military decoration or medal.[2] If convicted, defendants may be imprisoned for up to six months, unless the decoration lied about is the Medal of Honor, in which case imprisonment could be up to one year.”
So it was the act of making a false claim of having received a medal which was held to violate the First Amendment.
That’s not what the Canadian Criminal Code provision addresses. The provision makes it an offence to wear a uniform of the Canadian Armed Forces without lawful excuse, or to wear medals without lawful excuse. It doesn’t address the broader issue of false claims to have received a medal, which is what the first version of the Stolen Valor Act addressed, and which the SCOTUS struck down. The Criminal Code is completely silent on someone making a false claim to have received a medal, so there is no parallel between the charges faced by Franck in Canada, and the charge faced by Alvarez in the US case.
The more accurate comparison is between s. 419 of the Criminal Code, quoted upthread, and 18 USC § 702.
Section 419 prohibits the wearing of Canadian Armed Forces uniforms and medals, without lawful excuse.
18 USC § 702 reads:
[QUOTE=Congress of the United States]
Whoever, in any place within the jurisdiction of the United States or in the Canal Zone, without authority, wears the uniform or a distinctive part thereof or anything similar to a distinctive part of the uniform of any of the armed forces of the United States, Public Health Service or any auxiliary of such, shall be fined under this title or imprisoned not more than six months, or both.
[/QUOTE]
So, US federal law similarly prohibits the wearing of a US military uniform, without authority. And guess what?
[QUOTE=Justice Black]
Our previous cases would seem to make it clear that 18 U.S.C. 702, making it an offense to wear our military uniforms without authority is, standing alone, a valid statute on its face.
[/QUOTE]
(*Schacht v. United States, 398 U.S. 58 at 61(1970)*.)
So, on the issue of a federal law which prohibits someone from wearing a federal uniform without lawful authority, the US and Canadian statutes appear to be similar in effect. And, the SCOTUS has held that the US federal offence of wearing a US military uniform without authority is “a valid statute on its face.”