What version of bat are you using?
bat 0.17.1

Describe the bug you encountered:
I Have a file with read permission:
.rw-r--r-- 7,0k myuser 14 Jan 23:16 .zshrc

I tried to read normally (with the file owner)
batcat .zshrc
[bat error]: '.zshrc': Permission denied (os error 13)

I retried using sudo:
sudo batcat /home/myuser/.zshrc
[bat error]: '/home/myuser/.zshrc': Permission denied (os error 13)

...

What did you expect to happen instead?
show the file contents
...

How did you install bat?
using the snap package

Environment

system

$ uname -srm
Linux 5.4.0-26-generic x86_64

$ lsb_release -a
No LSB modules are available.
Distributor ID: Linuxmint
Description: Linux Mint 20
Release: 20
Codename: ulyana

bat

$ batcat --version
bat 0.17.1

$ env
PAGER=less

bat_config

bat_wrapper

No wrapper script for 'bat'.

No wrapper script for 'batcat'.

bat_wrapper_function

No wrapper function for 'bat'.

No wrapper function for 'cat'.

No wrapper function for 'batcat'.

tool

$ less --version
less 551 (GNU regular expressions)