There is some latitude with regard to ISO sensitivity. Digital cameras often are less sensitive than the rated "base" sensitivity. The manufacturers tend to round up, possibly because it can make test results look better than they actually are. It also helps to preserve detail in the highlights. With film the manufacturers tend to round the sensitivity down.
With either film or digital the response curve from the darkest to lightest details to which the camera is sensitive can vary from one camera (digital) or film to the next. Even if the midtones are exposed identically, the highlights may be brighter or darker from one film to the next or from one digital camera to the next. The same is true for the shadows.
Then there's the whole reciprocity error (Schwarzschild effect) thing with film when exposing for longer than about one second.
Unless the exposure times were long enough that the Schwarzschild effect comes into play (and your recent comment indicates they weren't), your specific case to me seems to most likely be due to overexposure of the film when shot or over development of the film. The reason the digital images are not also overexposed may be due, in part, the lower sensitivity of the digital camera at the same ISO setting but is probably most influenced by a processing algorithm such as Canon's Auto Lighting Optimizer or an Auto setting in the profile used by Adobe Camera Raw that alters the gamma curves when converting the raw data based on the content of the scene.
To be more specific regarding the case of the example photos in the question: ACR ignores most of the "maker notes" section of the EXIF data that save the in-camera settings at the time the photo was taken. When you opened the raw files in ACR the default profile ACR used to interpret the data in the raw files likely applied some automatic adjustments to prevent displaying the brightest values in the raw data as blown highlights. It likely did the digital equivalent of reducing the development time of the analog negative to prevent blowing the highlights. But your analog negatives were developed without such a consideration for the overexposed highlights.
Had you opened the same raw files in Canon's Digital Photo Professional with the Neutral picture style applied, Auto Lighting Optimizer disabled, and everything else (brightness, contrast, highlights, shadow, etc.) set to "0" you would probably have gotten results much closer to what the film lab gave you than you did using ACR with an unknown profile applied.
Remember, there is almost always more information in a raw image file than can be displayed on an 8-bit monitor. This is particularly the case with images of high dynamic range scenes. So when you open a raw file in ACR, or any other application that displays an image from the data in a raw file, what you see on the screen is only one interpretation of that data. You're not actually looking at the data itself.